A multi-object distance, low distortion, high-definition machine vision lens and camera device

Abstract

The present invention provides a multi-object distance, low distortion, high-definition machine vision lens and camera device, wherein the lens comprises an optical system, the optical system comprises a first lens group, an aperture stop and a second lens group arranged on the same optical axis from the object side to the image side, the first lens group comprises a first lens, a second lens, a third lens and a fourth lens arranged on the same optical axis from the object side to the image side, and the second lens group comprises a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens and a tenth lens arranged on the same optical axis from the object side to the image side. The present invention can present an imaging effect of high image quality, high accuracy and low distortion while satisfying multiple object distances.

Description

Technical Field

[0001] The invention relates to the technical field of industrial lenses, and in particular to a multi-object distance, low distortion, high-definition machine vision lens and a camera device. Background Art

[0002] In recent years, with the development of the automation industry, machine vision has achieved rapid growth, and its application has become more extensive. As industrial lenses have the characteristics of high resolution, high definition and good stability, they can be used in many fields such as industry, medical, military, security, and intelligent transportation. In order to achieve good image acquisition and analysis functions, such industrial lenses usually require high-definition resolution to obtain the image characteristics of the object being photographed, and require high relative illumination to ensure the uniformity of the illumination of the picture. At the same time, in order to make the lens have good imaging effects at different working distances, the lens needs to collect images at different working distances by focusing.

[0003] However, most industrial lenses on the market nowadays are difficult to meet and present imaging effects with high image quality, high accuracy and low distortion at multiple object distances. Summary of the invention

[0004] In order to solve the above problems in the prior art, the present invention provides a multi-object distance, low distortion, high-definition machine vision lens and camera device, which can present an imaging effect with high image quality, high accuracy and low distortion under the condition of meeting multiple object distances.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] In a first aspect, the present invention provides a multi-object distance, low distortion, high-definition machine vision lens, comprising an optical system, wherein the optical system comprises a first lens group, an aperture stop, and a second lens group arranged on the same optical axis from the object side to the image side, wherein the first lens group comprises a first lens, a second lens, a third lens, and a fourth lens arranged on the same optical axis from the object side to the image side, and the second lens group comprises a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens arranged on the same optical axis from the object side to the image side;

[0007] The first lens is a meniscus lens with negative optical power, the second lens is a plano-concave lens with negative optical power, the third lens is a biconvex lens with positive optical power, the fourth lens is a meniscus lens with negative optical power, the fifth lens is a biconvex lens with positive optical power, the sixth lens is a biconcave lens with negative optical power, the seventh lens is a plano-convex lens with positive optical power, the eighth lens is a biconcave lens with negative optical power, the ninth lens is a meniscus lens with positive optical power, and the tenth lens is a biconvex lens with positive optical power.

[0008] The beneficial effects of the present invention are: the focal length of the optical module is 16mm, the resolution can reach 250lp / mm, and the full-field optical distortion is less than 0.13%; it adopts a floating focus system, has a high level of imaging quality, is suitable for occasions under different object distances, can effectively reduce optical defects such as chromatic aberration and aberration of the telephoto lens, reduce distortion, and improve imaging clarity and accuracy, thereby presenting an imaging effect with high image quality, high accuracy, and low distortion under the condition of meeting multiple object distances.

[0009] Optionally, the focal length F1 of the first lens, the focal length F2 of the second lens, the focal length F3 of the third lens, the focal length F4 of the fourth lens, the focal length F5 of the fifth lens, the focal length F6 of the sixth lens, the focal length F7 of the seventh lens, the focal length F8 of the eighth lens, the focal length F9 of the ninth lens, the focal length F10 of the tenth lens and the total focal length F of the optical system composed thereof satisfy the following focal length relationship:

[0010] -2.6 <F1 / F<-2;

[0011] -2 <F2 / F<-1.5;

[0012] 0.5 <F3 / F<1;

[0013] -1.5 <F4 / F<-1;

[0014] 0.4 <F5 / F<0.9;

[0015] -0.8 <F6 / F<-0.5;

[0016] 0.8 <F7 / F<1.2;

[0017] 1.6 <F9 / F<2.2;

[0018] 1 <F10 / F<1.5。

[0019] Optionally, the total optical length TTL of the lens and the maximum image height IH corresponding to the maximum field angle of the lens satisfy:

[0020] 5.4≤TTL / IH≤6.

[0021] Optionally, the back focal length BFL of the lens and the total focal length F of the optical system satisfy:

[0022] 0.4≤BFL / F≤0.9.

[0023] Optionally, the air gap between the first lens and the second lens is 2.2 mm, the air gap between the second lens and the third lens is 5.5 mm, the air gap between the third lens and the fourth lens is 0 mm, the air gap between the fourth lens and the aperture stop is 8.0 mm, the air gap between the aperture stop and the fifth lens is 1.8 mm, the air gap between the fifth lens and the sixth lens is 0 mm, the air gap between the sixth lens and the seventh lens is 0.9 mm, the air gap between the seventh lens and the eighth lens is 0 mm, the air gap between the eighth lens and the ninth lens is 0.6 mm, the air gap between the ninth lens and the tenth lens is 0.2 mm, and the air gap between the tenth lens and the imaging plane is 13.7 mm.

[0024] Optionally, the first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens and the tenth lens are all spherical lenses made of glass.

[0025] Optionally, the first lens group and the second lens group are floating focus, and the adapted object distance range is greater than 100 mm.

[0026] In a second aspect, the present invention provides a camera device, comprising a photosensitive component and the lens of the first aspect;

[0027] The lens is mounted on the photosensitive component so that the photosensitive component is suitable for receiving light passing through the optical system and outputting imaging data.

[0028] Among them, the technical effect corresponding to the camera device provided in the second aspect refers to the relevant description of the multi-object distance, low distortion, high-definition machine vision lens provided in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 Schematic diagram of the optical structure of a multi-object distance, low distortion, high-definition machine vision lens according to an embodiment of the present invention;

[0030] Figure 2 A modulation transfer function curve diagram of a multi-object distance, low distortion, high-definition machine vision lens according to an embodiment of the present invention;

[0031] Figure 3 It is a distortion curve diagram of a multi-object distance, low distortion, high-definition machine vision lens according to an embodiment of the present invention;

[0032] Figure 4It is a relative illumination curve of a multi-object distance, low distortion, high-definition machine vision lens according to an embodiment of the present invention.

[0033] Description of reference numerals:

[0034] L1, first lens group; L2, second lens group;

[0035] 1. First lens; 2. Second lens; 3. Third lens; 4. Fourth lens; 5. Fifth lens; 6. Sixth lens; 7. Seventh lens; 8. Eighth lens; 9. Ninth lens; 10. Tenth lens; 11. Aperture stop; 12. Imaging surface. DETAILED DESCRIPTION

[0036] In order to better understand the above technical solution, exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a clearer and more thorough understanding of the present invention and to fully convey the scope of the present invention to those skilled in the art.

[0037] Embodiment 1

[0038] Please refer to Figure 1 A machine vision lens with multiple object distances, low distortion and high definition, comprising an optical system, the optical system comprising a first lens group L1, an aperture stop 11 and a second lens group L2 arranged on the same optical axis from the object side to the image side, the first lens group L1 comprising a first lens 1, a second lens 2, a third lens 3 and a fourth lens 4 arranged on the same optical axis from the object side to the image side, the second lens group L2 comprising a fifth lens 5, a sixth lens 6, a seventh lens 7, an eighth lens 8, a ninth lens 9 and a fourth lens 10 arranged on the same optical axis from the object side to the image side Ten lenses 10; the first lens 1 is a meniscus lens with negative optical power, the second lens 2 is a plano-concave lens with negative optical power, the third lens 3 is a biconvex lens with positive optical power, the fourth lens 4 is a meniscus lens with negative optical power, the fifth lens 5 is a biconvex lens with positive optical power, the sixth lens 6 is a biconcave lens with negative optical power, the seventh lens 7 is a plano-convex lens with positive optical power, the eighth lens 8 is a biconcave lens with negative optical power, the ninth lens 9 is a meniscus lens with positive optical power, and the tenth lens 10 is a biconvex lens with positive optical power.

[0039] In this embodiment, the focal length F1 of the first lens 1, the focal length F2 of the second lens 2, the focal length F3 of the third lens 3, the focal length F4 of the fourth lens 4, the focal length F5 of the fifth lens 5, the focal length F6 of the sixth lens 6, the focal length F7 of the seventh lens 7, the focal length F8 of the eighth lens 8, the focal length F9 of the ninth lens 9, the focal length F10 of the tenth lens 10 and the total focal length F of the optical system composed thereof satisfy the following focal length relationship:

[0040] -2.6 <F1 / F<-2;

[0041] -2 <F2 / F<-1.5;

[0042] 0.5 <F3 / F<1;

[0043] -1.5 <F4 / F<-1;

[0044] 0.4 <F5 / F<0.9;

[0045] -0.8 <F6 / F<-0.5;

[0046] 0.8 <F7 / F<1.2;

[0047] 1.6 <F9 / F<2.2;

[0048] 1 <F10 / F<1.5。

[0049] In this embodiment, the air gap between the first lens 1 and the second lens 2 is 2.2 mm, the air gap between the second lens 2 and the third lens 3 is 5.5 mm, the air gap between the third lens 3 and the fourth lens 4 is 0 mm, the air gap between the fourth lens 4 and the aperture stop 11 is 8.0 mm, the air gap between the aperture stop 11 and the fifth lens 5 is 1.8 mm, the air gap between the fifth lens 5 and the sixth lens 6 is 0 mm, the air gap between the sixth lens 6 and the seventh lens 7 is 0.9 mm, the air gap between the seventh lens 7 and the eighth lens 8 is 0 mm, the air gap between the eighth lens 8 and the ninth lens 9 is 0.6 mm, the air gap between the ninth lens 9 and the tenth lens 10 is 0.2 mm, and the air gap between the tenth lens 10 and the imaging plane 12 is 13.7 mm.

[0050] In this embodiment, the first lens 1, the second lens 2, the third lens 3, the fourth lens 4, the fifth lens 5, the sixth lens 6, the seventh lens 7, the eighth lens 8, the ninth lens 9 and the tenth lens 10 are all spherical lenses made of glass, which are easy to process and detect.

[0051] In this embodiment, the total optical length TTL of the lens and the maximum image height IH corresponding to the maximum field angle of the lens satisfy: 5.4≤TTL / IH≤6. The back focal length BFL of the lens and the total focal length F of the optical system satisfy: 0.4≤BFL / F≤0.9.

[0052] The optical parameters of each lens in this embodiment are shown in Table 1 below.

[0053] Table 1

[0054]

[0055] The surface numbers in Table 1 are arranged in order from the object side to the image side. When the surface is a plane, the radius corresponds to infinity. The air gap between the third lens 3 and the fourth lens 4, the air gap between the fifth lens 5 and the sixth lens 6, and the air gap between the seventh lens 7 and the eighth lens 8 are all 0 mm, that is, the two are attached. Therefore, there is only one surface here, and there are 18 surfaces in total.

[0056] Therefore, in this embodiment, the effective focal length of the lens is 16 mm, the relative numerical aperture is F / 2.8, the full field angle is 37.6°, the diagonal size of the imaging surface 12 is 11 mm, the total optical length is 62.1 mm from the first lens 1 to the imaging surface 12, and the operating band is 400 nm-700 nm.

[0057] The present invention adopts a floating focus structure of the first lens group L1 and the second lens group L2, has a high level of image quality, is suitable for occasions with different object distances, can match the length of the lens extension, move a whole group of lenses, effectively reduce optical defects such as chromatic aberration and aberration of the telephoto lens, reduce distortion, improve the clarity and accuracy of imaging, and make it adaptable to the object distance range of 100mm to infinity, realize clear imaging of a large target surface of 2 / 3 inches, realize a wide working distance, can match the work of detection equipment of various manufacturers, and has a reasonable structure.

[0058] like Figure 2 As shown, the cut-off frequency of the multi-object distance, low-distortion, high-definition machine vision lens of this embodiment at the full field of view is 250lp / mm, the corresponding modulation transfer function value is better than 0.2, and the modulation transfer function curves of each field of view are relatively concentrated, indicating that the small-volume, multi-object distance, low-distortion, high-definition machine vision lens of this embodiment can achieve high-precision detection of targets. Wherein, OTF is the optical transfer function.

[0059] like Figure 3 As shown, the distortion value of a multi-object distance, low distortion, high-definition machine vision lens of this embodiment is less than 0.13% within the full field of view, which effectively reduces optical defects such as chromatic aberration and aberration of the lens, reduces distortion, and improves the clarity and accuracy of imaging.

[0060] like Figure 4 As shown, the relative illumination value of the multi-object distance, low distortion, high-definition machine vision lens of this embodiment in the whole field of view is greater than 92.1%, which avoids the occurrence of dark corners and ensures the uniformity of the picture illumination.

[0061] Embodiment 2

[0062] This embodiment provides a camera device, including a photosensitive component and a multi-object distance, low distortion, high-definition machine vision lens in Embodiment 1. The lens is mounted on the photosensitive component, so that the photosensitive component is suitable for receiving light passing through the optical system and outputting imaging data.

[0063] In summary, the machine vision lens of this embodiment has the characteristics of small size, multiple object distances, low distortion, high definition, large target surface, wide working distance and high-precision detection.

[0064] In the description of the present invention, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0065] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0066] In the present invention, unless otherwise clearly specified and limited, when a first feature is “on” or “below” a second feature, it may be that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, when a first feature is “above”, “above” or “above” a second feature, it may be that the first feature is directly above or obliquely above the second feature, or it may simply mean that the first feature is higher in level than the second feature. When a first feature is “below”, “below” or “below” a second feature, it may be that the first feature is directly below or obliquely below the second feature, or it may simply mean that the first feature is lower in level than the second feature.

[0067] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, unless they are contradictory.

[0068] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may alter, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A multi-object distance, low distortion, high-definition machine vision lens, characterized in that: An optical system is included, wherein the optical system only includes a first lens group, an aperture stop, and a second lens group which are arranged on the same optical axis from the object side to the image side, wherein the first lens group only includes a first lens, a second lens, a third lens, and a fourth lens which are arranged on the same optical axis from the object side to the image side, and the second lens group only includes a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, and a tenth lens which are arranged on the same optical axis from the object side to the image side; The first lens is a meniscus lens with negative optical power, the second lens is a plano-concave lens with negative optical power, the third lens is a biconvex lens with positive optical power, the fourth lens is a meniscus lens with negative optical power, the fifth lens is a biconvex lens with positive optical power, the sixth lens is a biconcave lens with negative optical power, the seventh lens is a plano-convex lens with positive optical power, the eighth lens is a biconcave lens with negative optical power, the ninth lens is a meniscus lens with positive optical power, and the tenth lens is a biconvex lens with positive optical power.

2. The multi-object distance, low distortion, high-definition machine vision lens according to claim 1, characterized in that: The focal length F1 of the first lens, the focal length F2 of the second lens, the focal length F3 of the third lens, the focal length F4 of the fourth lens, the focal length F5 of the fifth lens, the focal length F6 of the sixth lens, the focal length F7 of the seventh lens, the focal length F8 of the eighth lens, the focal length F9 of the ninth lens, the focal length F10 of the tenth lens and the total focal length F of the optical system composed thereof satisfy the following focal length relationship: -2.6 <F1 / F<-2; -2 <F2 / F<-1.5; 0.5 <F3 / F<1; -1.5 <F4 / F<-1; 0.4 <F5 / F<0.9; -0.8 <F6 / F<-0.5; 0.8 <F7 / F<1.2; 1.6 <F9 / F<2.2; 1 <F10 / F<1.5。 3. The multi-object distance, low distortion, high-definition machine vision lens according to claim 2, characterized in that: The total optical length TTL of the lens and the maximum image height IH corresponding to the maximum field of view of the lens satisfy: 5.4≤TTL / IH≤6.

4. The multi-object distance, low distortion, high-definition machine vision lens according to claim 3, characterized in that: The back focal length BFL of the lens and the total focal length F of the optical system satisfy: 0.4≤BFL / F≤0.

9.

5. A multi-object distance, low distortion, high-definition machine vision lens according to any one of claims 2 to 4, characterized in that: The air gap between the first lens and the second lens is 2.2 mm, the air gap between the second lens and the third lens is 5.5 mm, the air gap between the third lens and the fourth lens is 0 mm, the air gap between the fourth lens and the aperture stop is 8.0 mm, the air gap between the aperture stop and the fifth lens is 1.8 mm, the air gap between the fifth lens and the sixth lens is 0 mm, the air gap between the sixth lens and the seventh lens is 0.9 mm, the air gap between the seventh lens and the eighth lens is 0 mm, the air gap between the eighth lens and the ninth lens is 0.6 mm, the air gap between the ninth lens and the tenth lens is 0.2 mm, and the air gap between the tenth lens and the imaging plane is 13.7 mm.

6. The multi-object distance, low distortion, high-definition machine vision lens according to claim 5, characterized in that: The first lens, the second lens, the third lens, the fourth lens, the fifth lens, the sixth lens, the seventh lens, the eighth lens, the ninth lens and the tenth lens are all spherical lenses made of glass.

7. The multi-object distance, low distortion, high-definition machine vision lens according to claim 6, characterized in that: The first lens group and the second lens group are in floating focus, and the adapted object distance range is greater than 100 mm.

8. A camera device, characterized in that: Comprising a photosensitive component and the lens according to any one of claims 1 to 7; The lens is mounted on the photosensitive component so that the photosensitive component is suitable for receiving light passing through the optical system and outputting imaging data.

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